// Guarded Allocation -*- C++ -*- // Copyright (C) 2014-2019 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 3, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // . /** @file bits/allocated_ptr.h * This is an internal header file, included by other library headers. * Do not attempt to use it directly. @headername{memory} */ #ifndef _ALLOCATED_PTR_H #define _ALLOCATED_PTR_H 1 #if __cplusplus < 201103L # include #else # include # include # include namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION /// Non-standard RAII type for managing pointers obtained from allocators. template struct __allocated_ptr { using pointer = typename allocator_traits<_Alloc>::pointer; using value_type = typename allocator_traits<_Alloc>::value_type; /// Take ownership of __ptr __allocated_ptr(_Alloc& __a, pointer __ptr) noexcept : _M_alloc(std::__addressof(__a)), _M_ptr(__ptr) { } /// Convert __ptr to allocator's pointer type and take ownership of it template>> __allocated_ptr(_Alloc& __a, _Ptr __ptr) : _M_alloc(std::__addressof(__a)), _M_ptr(pointer_traits::pointer_to(*__ptr)) { } /// Transfer ownership of the owned pointer __allocated_ptr(__allocated_ptr&& __gd) noexcept : _M_alloc(__gd._M_alloc), _M_ptr(__gd._M_ptr) { __gd._M_ptr = nullptr; } /// Deallocate the owned pointer ~__allocated_ptr() { if (_M_ptr != nullptr) std::allocator_traits<_Alloc>::deallocate(*_M_alloc, _M_ptr, 1); } /// Release ownership of the owned pointer __allocated_ptr& operator=(std::nullptr_t) noexcept { _M_ptr = nullptr; return *this; } /// Get the address that the owned pointer refers to. value_type* get() { return std::__to_address(_M_ptr); } private: _Alloc* _M_alloc; pointer _M_ptr; }; /// Allocate space for a single object using __a template __allocated_ptr<_Alloc> __allocate_guarded(_Alloc& __a) { return { __a, std::allocator_traits<_Alloc>::allocate(__a, 1) }; } _GLIBCXX_END_NAMESPACE_VERSION } // namespace std #endif #endif